The last post reported on 33 climate trends discussed in “State of the Climate 2017,” a report published in the Bulletin of the American Meteorological Society. This post characterizes the 2017 climate in the United States. Be sure to catch that this is for 2017, not 2018, the year just ended. In what follows, “CONUS” means the continental United States. All anomalies compare to the 1981-2010 average.
The annual average temperature in 2017 for the contiguous United States (CONUS) was 12.5°C or 1.0°C above the 1981–2010 average—its third warmest year since records began in 1895, 0.2°C cooler than 2016 and 0.4°C cooler than 2012. Figure 1 shows a map of 2017 temperature anomaly across the United States. Every state was warmer than average except for Washington. Most of Missouri was 1.0-1.5°C warmer than average (1.8-2.7°F). A few areas were even warmer, but the map isn’t sufficiently detailed to determine for sure which areas they were.
Averaged nationally, precipitation was 104% of average, making 2017 the 20th wettest year in the record. The pattern was variable, however, as shown in Figure 2. In particular, winter precipitation was higher than average, with Nevada and Wyoming each having the wettest winters on record. The California mountains were wetter than average (I reported on the large snowpack in the winter of 2017 in previous posts). So was eastern Colorado-New Mexico. On the other hand, much of the Southwest and the northern Plain States were in drought. It was also dry along the Mississippi River from the Missouri Bootheel into central Iowa.
There were 16 weather-related events in 2017 which resulted in damage of more than $1 billion. That tied with 2011 for the highest number of billion-dollar disasters. The total damages they caused was $306 billion, a new record. Figure 3 shows a map of where they were roughly located. There were three major hurricanes across the southern United States, plus catastrophic fires in California and other western states. Missouri and Arkansas were affected by flooding in late April-early May 2017.
Missouri had 13 fatalities and 155 injuries from weather-related disasters in 2017, and a total of $156.20 million in damages. There have been many years when the Missouri’s weather-related damage has been below $100 million, but in 2011 it was over $3.4 billion.
Blunden, J., D. S. Arndt, and G. Hartfield , Eds., 2018: State of the Climate in 2017. Bull. Amer. Meteor. Soc., 99 (8), Si–S332, doi:10.1175/2018BAMSStateoftheClimate.1. Downloaded 12/15/18 from https://www.ametsoc.org/index.cfm/ams/publications/bulletin-of-the-american-meteorological-society-bams/state-of-the-climate.
Office of Climate, Water, and Weather Services, National Weather Service. 2016. Natural Hazard Statistics. Data downloaded 2/10/16 from http://www.nws.noaa.gov/om/hazstats.shtml#.
The IPCC report Global Warming of 1.5°C, and the Fourth National Climate Assessment were not the only climate related reports to be published in the second half of 2018. The American Meteorological Society also published its annual report on the climate, State of the Climate in 2017. Rather than a document assessing the effects of climate change, this documents presents a comprehensive picture of what the climate was like in 2017.
Figure 1 shows in a single graphic the major climate variables that are discussed in the report. I will discuss each very briefly in order, going down each column before moving to the next column. I’ve made the chart to open in a separate browser tab, and you should be able to refer back and forth between my comments and the charts. In the charts, some of the data is shown as anomalies rather than as raw values, and in those cases, the reference period is given in the chart.
Charts (a) and (b) show the level of polar ozone, the 1st in March, the 2nd in October. This ozone is high-altitude ozone, and it is essential for blocking ultraviolet rays, too much of which are harmful. These charts concern the famous ozone hole of the 1980s. In general, the level in March bottomed in the 1980s, partially rebounded, but has again been trending downward. In October, the level bottomed in the 1980s and has been largely moving sideways since then.
Chart (c) shows the average surface temperature in the arctic. It has obviously been warming, some 3°C since the 1950s.
Chart (d) shows the average surface temperature of the whole earth. It has been warming, but not as much as the arctic. The recent several years show a steep spike upward.
Chart (e) shows temperature in the lower troposphere. This is the lowest layer of the earth’s atmosphere, and it is where almost all life occurs, as well as almost all weather. It has been warming, and you can see the same spike in recent years.
Chart (f) shows the temperature in the lower stratosphere. This is the next higher layer of the atmosphere. Near the equator it begins some 66,000 feet up, while at the poles it is lower, some 23,000 feet up. The temperature here has been cooling. I have seen some arguments that the cooling in the stratosphere compensates for the heat in the troposphere. This is like saying that cool weather in San Francisco means people can’t be dying from a heat wave in Chicago. Sorry, but it doesn’t mean any such thing.
Chart (g) plots the number of warm days (solid line) and cool nights (dotted line). Warm days have been increasing, and cool nights have been decreasing.
Chart (h) shows the area covered by arctic sea ice. The maximum is the solid line, the minimum the dotted line. Both have been decreasing, the minimum more severely.
Chart (i) shows antarctic sea ice. The variability between years has grown significantly, and the general trend appears to be increasing.
Chart (j) shows a measure of the amount of water locked-up as ice in all of the world’s glaciers. It has been declining at a significant rate. It will have implications for anyone and anything dependent on glaciers and/or glacial melt for water.
Chart (l) shows the amount of water vapor in the lower stratosphere. It is quite variable, but the trend appears to be toward slightly higher amounts of water vapor.
Chart (m) shows the level of cloudiness across the planet. There are several data sets. The trend appears to be towards convergence, with a slightly downward slope for at least some of the data sets.
Chart (n) shows the amount of water vapor in the entire atmosphere, top to bottom, over land. It has been increasing.
Chart (o) shows the amount of water vapor in the entire atmosphere, top to bottom, over the ocean. It, too, has been increasing.
Chart (p) shows the specific humidity in the upper troposphere. It appears to be declining slightly.
Chart (q) shows the specific humidity over land. It has been increasing. Specific humidity is not the humidity statistic we are used to, that is relative humidity (see below). The specific humidity is a measure of the mass of water vapor in an air sample compared to the mass of the other air in the sample.
Chart (r) shows the specific humidity over the ocean. It, too has been increasing.
Chart (s) shows relative humidity over the land. It has been decreasing. Relative humidity is a measure of the amount of water a sample of air is holding, compared to the maximum it could hold. Air’s ability to hold water increases with temperature, so it is possible for relative humidity to decrease, even while specific humidity increases, if the temperature rises.
Chart (t) Shows relative humidity over the ocean. It has been mostly moving sideways, but perhaps decreasing slightly.
Chart (u) shows the amount of precipitation over land. It moved mostly sideways until the 1980s, at which point it appears to have increased. The recent years have seen a significant spike upward.
Chart (v) shows the Southern Oscillation Index. This is a measure comparing air pressure in the western and eastern South Pacific. It tracks the El Niño phenomenon, with negative values indicating an El Niño, and positive values indicating a La Niña. I see no obvious trend in the data.
Chart shows the amount of heat the ocean is holding. The amount of heat is not the same as the temperature: a 100° pot of water holds much more heat than a 100° pot of air, though both are the same size. The heat content of the oceans has bee increasing.
Chart (x) shows a measure of sea level. It has been rising. The scale is in millimeters, so the chart shows about a 6-inch rise.
Chart (y) shows the tropospheric ozone level in the tropics. It has been increasing. This is not the same as arctic ozone levels, which are measured in the stratosphere, where they help to block ultraviolet light from striking the earth. This is ground level ozone, a harmful pollutant. It is the ozone I track when I report on the Air Quality Index.
Chart (z) shows a measure of the speed of the wind in the troposphere. It has been increasing slightly.
Chart (aa) shows a measure of the speed of the wind over land. It has been decreasing.
Chart (ab) shows a measure of the speed of the wind over the ocean. It has been increasing.
Chart (ac) shows the amount of biomass being burned each year. It has been deecreasing.
Chart (ad) shows a measure of soil moisture across the earth. It has been moving sideways, a surprise to me, as I would have expected increased temperatures to dry the soil.
Chart (ae) shows terrestrial water storage. Though the data series is short, it appears to be declining. This variable concerns fresh water, and reflects ice sheets, glaciers, and lakes. Its decline is a matter of concern for all people, animals, and plants that depend on stored water.
Chart (af) shows global FAPAR. FAPAR is the amount of solar radiation available for absorption by plants during photosynthesis that actually gets absorbed. Though the data series is short, it was declining, but in recent years it has increased.
Chart (ag) shows the albedo of the land surface. Though the data series is short, it appears to be decreasing. Albedo is the reflectivity of the earth. High albedo means most of the light is reflected. Low albedo means most of the light is absorbed, causing the surface to warm. Black paint has a low albedo, white paint has a high albedo.
Blunden, J., D. S. Arndt, and G. Hartfield , Eds., 2018: State of the Climate in 2017. Bull. Amer. Meteor. Soc., 99 (8), Si–S332, doi:10.1175/2018BAMSStateoftheClimate.1.
In my previous post I reported on the 4th National Climate Assessment, Volume 1. That volume deals with the natural science findings. Volume 2 deals with how climate change is projected to impact the United States, and with mitigation and adaptation. Unlike reports by the IPCC, the National Climate Assessment focuses on the United States. As with all of the IPCC and NCA reports, the 4th National Climate Assessment is far too large and substantive to fully summarize in a brief blog post. What follows is a selection of a few of the findings.
Figure 1 projects U.S. economic damage from climate change in 2090 under the low emission scenario (RCP 4.5) and the high emission scenario (8.5). The intangibles that make life worth living, what we call quality of life, are not easy to put a dollar value on, and this chart does not address them.
In the chart, the columns represent various sectors of the economy. The blue portion represents the damages under RCP 4.5, while the whole column represents the damages under RCP 8.5 Thus, the orange portion represents the difference between the two. The largest economic damages come from 3 sectors: Labor, Extreme Temperature Mortality, and Coastal Property. In addition, in most of the sectors, the damages under RCP 8.5 are more than twice the damages under RCP 4.5.
(Click on chart for larger view.)
Figure 2 shows projected carbon emissions, temperature change, and U.S. economic damage from climate change under various emission scenarios. The left side of the chart shows that observed carbon emissions are following the high scenario, and there is no evidence that they are suddenly about to revert to the low emission scenario. The right side shows that the high emissions scenarios lead to larger increases in temperature and correspondingly larger damages to the U.S. economy.
The Overview of the report summarizes some of the specific risks the USA faces from climate change. It is quite a list, but it puts real form to projections that often are statistical or vague. To paraphrase:
- Rising sea levels, higher storm surges, and increased high tide flooding will impact coastal infrastructure, damaging electrical and natural gas supply lines, and causing problems with access to goods from overseas. About $1 trillion in coastal property will be impacted. Coastal cities will experience daily flooding.
- Wildfire in the West will increase, damaging ranches and rangelands; increasingly it will damage property in cities and take human lives. Energy transmission and production will be damaged.
- Thawing permafrost in Alaska will damage roads and buildings, including oil and gas operations. This will be partially offset by a longer ice-free season.
- Yields of major U.S. crops (corn, soybeans, wheat, rice, sorghum, and cotton) are expected to decline due to higher temperatures and changes in water availability, disease, and pests. These will percolate through the economy, resulting in less availability of agricultural products, and increased prices.
- Human productivity equal to almost 2 billion labor hours is expected to be lost annually due to extreme temperatures, resulting in an estimated $160 billion in lost wages. States in the Southeast and Southern Great Plains are expected to be impacted hardest.
- Fresh water quality and quantity are threatened by rising temperatures, reduced mountain snowpack, sea level rise, saltwater intrusion, drought, flooding, and algal blooms. In some places, the availability of safe and dependable water will be threatened.
- Hydropower supplies are expected to decrease as a result of changes in mountain snowpack.
- Drought will impact oil and gas drilling and refining, all of which use water intensely.
- Tourism will be impacted by changes in snowpack and wildfire. Communities dependent on tourism will be impacted.
- Air quality will be impacted by higher temperature, higher humidity, and increased smoke from wildfires. Reduced air quality is expected to adversely impact human health.
- Species already are, and will continue, to shift their growing ranges and growing seasons in response to climate change. Mismatches between species and the availability of the resources they need to survive are expected to occur. Extinctions and transformative impacts on some ecosystems are expected.
- Heavy-to-severe coral bleaching is expected to onset across most of the Hawaiian Islands, Guam, and American Samoa by the late 2030s. This will impact fisheries yields and tourism. (Paradise Lost – where’s John Milton when you need him?)
- Rising temperatures are expected to increase illness and death (especially among older adults, pregnant women, and children), partially (but only partially) offset by a reduction in cold-weather deaths.
- Rising temperatures are expected to reduce electricity generation capacity while simultaneously increasing demand for it and its costs. Power outages and blackouts are expected to increase, and household budgets will be strained. Marginal populations and the economically disadvantaged will be impacted even more severely.
- Rising temperatures are expected to threaten human health by promoting the growth of foodborne and waterborne pathogens. Diseases like Lyme disease, West Nile, chikungunya, dengue, and Zika are expected to spread and become more common.
- Every armed service (but especially the Navy, Marines, and Coast Guard), has many bases located in coastal regions. They are expected to be threatened by climate change, and in some cases made unusable. Many of the transportation routes between these bases are similarly located in coastal regions and may become unusable. Thus, climate change is expected to become a significant challenge to the national security apparatus of this country.
- All of the above expected effects of climate change are expected to cause increased stress, leading to increased rates of stress-related diseases, including mental illness.
In terms of mitigation and adaptation, the report states that power sector emissions were 25% below 2005 levels in 2016, the largest emissions reduction for a sector of the American economy over this time. This decline was in large part due to increases in natural gas and renewable energy generation, as well as enhanced energy efficiency standards and programs. Under continued business-as-usual projections, U.S. carbon dioxide and other greenhouse gas emissions show flat or declining trajectories over the next decade with a central estimate of about 15% to 20% reduction below 2005 levels by 2025. (While it is great that U.S. emission have declined, worldwide emissions continue to increase.)
The report notes that efforts to adapt to climate change and to mitigate its effects have increased across the country, but are not even close to adequate. Adaptation is an issue for local planning, as it must take into account both the specific damages anticipated in the locale and many local characteristics such as topography, local water supply, etc. Mitigation follows pathways that are more common across different locations. Figure 3 shows is a map showing the number of GHG mitigation policies in place in each state, by type of policy.
The fact that Missouri has mitigation policies in place does not necessarily mean that GHG emissions have substantially decreased. I last reported on state GHG emissions using data from 2013. At that time, Missouri’s GHG emissions from fossil fuel were still above their level in 2000. Figure 4 republishes a chart from that post showing GHG emissions over time from Missouri and some neighboring states.
The document contains a great deal more than I can report in this post. Those who are interested can follow the link in the Sources section below to the original document. The whole document is available as a single download, or you can download individual chapters.
USGCRP, 2018: Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II [Reidmiller, D.R., C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 1515 pp. doi: 10.7930/NCA4.2018. Downloaded 12/5/2018 from https://nca2018.globalchange.gov.
The National Climate Assessment is the official United States Government report on climate change. The most recent assessment is the 4th one. It was issued in 2 volumes, the first of which was published in November, 2017. It focuses on the science of climate change and the changes that are likely to occur. The second volume was published in October, 2018. It focuses how the changes outlined in Volume 1 are projected to impact our country, and on some perspectives on adaptation.
In the remainder of this post, italics represent direct quotes from the Executive Summary of Volume 1. In parentheses, I give the page of the report where the quote can be found.
Global annually averaged surface air temperature has increased by about 1.8°F (1.0°C) over the last 115 years (1901–2016). This period is now the warmest in the history of modern civilization. (p.1) In Figure 1, the chart on the left presents a graph of the increase in temperature. The map on the right shows how the change in temperature is distributed across the world.
(Click on chart for larger view.)
The last three years have been the warmest years on record for the globe. These trends are expected to continue…(p.1) Figure 2 maps the projected increase in temperature across North America at mid- and late-century under a low emission scenario and a high emission scenario. I favor the high emission scenario, because I see no sign we are slowing GHG emissions. The high emission scenario shows the average yearly temperature rising by 4-6°F in Missouri by mid-century. By the end of the century, some regions of the country will experience temperature increases of 8-10°F.
Human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century. (p.1) There is no convincing alternative explanation. See the previous post for some comments on climate change denial.
Global average sea level has risen by about 7–8 inches since 1900, with almost half (about 3 inches) of that rise occurring since 1993. (p.1)
Global average sea levels are expected to continue to rise—by at least several inches in the next 15 years and by 1–4 feet by 2100. A rise of as much as 8 feet by 2100 cannot be ruled out. (p.2) Figure 3 shows historical and projected sea level rise across 2 time scales – the upper chart goes back to 500 BCE. The lower chart goes back to 1800. The upper one especially shows that the increase in sea level is unprecedented in human history. The different colored lines in the lower chart represent projections from different future emission scenarios – high (red) to low (blue).
The incidence of daily tidal flooding is accelerating in more than 25 Atlantic and Gulf Coast cities. (p.2) Figure 4 shows the historical and projected incidence of minor tidal flooding in Charleston SC, and San Francisco CA. Minor flooding is also called nuisance flooding. Basically, it is flooding that occurs only at high tide, and is limited to a couple of feet. But it is defined differently at different locations. For an article explaining it all, see here: https://www.climate.gov/news-features/understanding-climate/understanding-climate-billy-sweet-and-john-marra-explain. The charts show that flooding is on the increase, though in San Francisco, the increase is small (also typical of other West Coast locations). It is much larger in Charleston (also typical of other East Coast locations). In both locations, minor flooding is expected to increase, and under the high emission scenario, which is the one we seem to be following, it will nearly become a daily event.
Heavy rainfall is increasing in intensity and frequency across the United States and globally and is expected to continue to increase. The largest observed changes in the United States have occurred in the Northeast. (p.2) Figure 5 shows the historical change in heavy precipitation events across the United States. It shows the data in several forms. The map at upper left shows the percentage change in the largest 1-day rainfall event over rolling 5-year periods. The map at upper right shows the percentage change in the number of days that fall in the 99th percentile of 1-day precipitation over the historical record. The map at lower left shows the percentage change in the number of 2-day precipitation events that exceeded the largest 2-day amount that is expected to occur, on average, once every 5 years, from 1901-2016. The map at lower right shows the number of 2-day precipitation events that exceeded the largest 2-day amount that is expected to occur, on average, once every 5 years, from 1958-2016. Thus, the two lower maps show identical data, except the reference period in the left one stretches back to 1901, while the reference period in the right one stretches back to 1958. (This is all a bit complicated, but it is necessary because the amount of precipitation that constitutes a heavy event may be different in, say, Seattle vs. Las Vegas. You just have to unpack it slowly, and it all makes sense.)
The trend in Figure 4 is strongest in the eastern part of the country, where the increase is large, no matter how you count the data. In the Southwest, however, the data is equivocal. That region may be getting heavier 1-day storms, but heavy precipitation is not lasting over 2 days as frequently as it used to.
Heatwaves have become more frequent in the United States since the 1960s, while extreme cold temperatures and cold waves are less frequent. (p.2) I have written previous posts on how the increase in temperature could lead to deadly heat waves. One series of posts starts here. Another article is here.
The incidence of large forest fires in the western United States has increased…and is expected to further increase…with profound changes to regional ecosystems. (p.2) I’ve written quite a number of posts about how fire is increasing in the West, and how that may contrast with Missouri. See here and here.
Earlier spring melt and reduced snowpack are already affecting water resources in the western United States…Long-duration hydrological drought is increasingly possible before the end of this century. (p.2) I’ve covered this extensively in my posts on the water situation in California and made a number of updates. The original series of posts is here. The most recent update is here.
The magnitude of climate change…will depend primarily on the amount of greenhouse gases (especially carbon dioxide) emitted globally…With significant reductions…the increase in annual average global temperature could be limited to 3.6°F (2°C) or less. (p.2)
The global atmospheric carbon dioxide (CO2) concentration has now passed 400 parts per million (ppm), a level that last occurred about 3 million years ago, when both global average temperature and sea level were significantly higher than today. (p.2)
Continued CO2 emissions would lead to an atmospheric concentration not experienced in tens to hundreds of millions of years. (p.3)
In 2014 and 2015, emission growth rates slowed as economic growth became less carbon-intensive. A recent report, however, suggests that in 2018, the rate of emissions reversed, surging ahead at an accelerating rate. (Le Quéré et al, 2018)
The next post will focus on Volume 2 of the National Climate Report.
U.S. Global Change Research Program. 2017. Climate Science Special Report: Fourth National Climate Assessment, Volume I [Wuebbles, D.J., D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 470 pp, doi: 10.7930/J0J964J6.
Le Quéré, Corinne, and 76 other authors. 2018. Global Carbon Budge, 2018. Earth System Science Data, 10, 2141-2194. Downloaded 12/8/2018 from https://doi.org/10.5194/essd-10-2141-2018.
I ended my last post by noting that if we are to avoid devastating the planet and ourselves through climate change, drastic action is needed immediately. If you ask me, that’s been clear for a long time, but the truth has been denied by climate change deniers. Climate change deniers dislike the word “denial” because it comes from the psychological mechanism of denial, like addicts who deny that they have an addiction.
Perhaps climate change deniers do have an illness like addiction, or perhaps it is something even worse.
In a recent OpEd, Paul Krugman compares the denial of climate change to the denial that cigarette smoking is harmful. According to him, tobacco companies knew for decades that smoking was harmful, but undertook a cynical campaign to try to discredit the science around smoking. Why? Money. They were willing to let hundreds of thousands die in order to preserve profits. The denial of climate change, he says, has been undertaken by fossil fuel companies for precisely the same reason, using precisely the same tactics (and, in fact, using some of the same organizations to conduct the campaign). He also gives a nod to mistrust of government regulation, which will be required to address climate change (while also poking fun at it, noting that their mistrust somehow manages to allow governments to force consumers to subsidize coal. Thus, the real motivation is reduced back to money.) Krugman concludes that this is not just misguided, it is depraved.
The amazing thing is that their nonsense has taken hold of an entire political party (the Republicans) and a great number of people in this state (Missouri). It reminds one of how Naziism took hold of a large number of people in Germany during the 1930s. We look back and ask how rational people could have believed such obvious nonsense, such vile evil? Could such things happen in the USA? Well, try reading The Paranoid Style in American Politics for a starter. Of course it could.
The climate change deniers I have known fall into two camps. Some are simple people who are just repeating what they have heard their neighbors say, or what they have seen in the conservative media they like to follow. Others are more informed. These deniers like to see themselves as skeptics, but to me they seem pervasively suspicious, oppositional, and perhaps even querulous. They are preoccupied with unjustifiable doubts, often seeing conspiracies where none exist. They focus on details or outright fabrications to prop up their denial, while ignoring vast amounts of fact, upon which they turn their back. Because not everything is known, they argue that nothing is known.
I received an email from one, a British lord no less, who comfortably turned his back on thousands of scientific references in an IPCC report, in favor of a column written by the host of an Australian children’s TV show. Well, he claimed, climate science is a vast conspiracy.
Is that paranoia? Has it gone so far as to be a psychotic delusion? Were the German people who supported Naziism deluded? Psychotic? At what point does fear of the future – I’m fearful, too, it would be silly not to be – turn into suspicion and paranoia?
Well, this IPCC report makes it clear that global warming, if left unchecked, is going to cost hundreds of billions of dollars yearly, and is going to ruin the lives of hundreds of millions. Clinging on to denial in the face of such facts, Krugman writes, is depraved. It is no longer a viable intellectual or political position, he argues, it is a sign of depravity.
Drastic change is required immediately if we are to avoid terrible damage to our planet. Even in only economic terms, the projected damage if we do nothing is absolutely staggering. But in addition to that, the lives of hundreds of millions will be ruined. Can humankind respond with the kind of immediate, large-scale planetary change that is required, or is it already too late? Will we act, or have we sold ourselves out to the forces of depravity?
Hofstadter, Richard. 1996. The Paranoid Style in American Politics, and Other Essays. Cambridge, MA: Harvard University Press. Originally published in 1952.
Intergovernmental Panel on Climate Change. 2018. Global Warming of 1.5°C (Draft). Downloaded 11/24/2018 from https://www.ipcc.ch/report/sr15.
Krugman, Paul. “The Depravity of Climate-Change Denial.” The New York Times, November 26, 2018. Viewed online 12/1/2018 at https://www.nytimes.com/2018/11/26/opinion/climate-change-denial-republican.html.
In the previous post, I reported that the recent IPCC report, Global Warming of 1.5°C, concludes that it is theoretically possible to limit global warming to 1.5°C, but it would require drastic change: a 50% reduction in GHG emissions by 2030, and zero net GHG emissions by 2050. In this post, I will discuss some of what the report says about making such a change.
The IPCC reviewed a number of computer models to explore scenarios that limited global warming to 1.5°C. Assumptions varied between the models, and they consequently yielded different results. They can be grouped into several categories: models that projected an increase in Global Mean Surface Temperature (GMST) that stayed below 1.5°C, models that projected a small overshoot of 1.5°C (eventually returning to 1.5°C), models that projected a large overshoot of 1.5°C (eventually returning to 1.5°C), models that projected a 2.0°C increase in GMST, and models that projected a large increase above 2.0°C.
According to the report, limiting the increase in GMST to 1.5°F would require putting a substantial price on carbon emissions. Estimates vary widely, thus, there is substantial uncertainty about just how large the price increase would need to be. It is clear, however, that the smaller the increase in GMST, the higher the price would have to be, and in all cases, the price would need to rise over time. Figure 1 shows the findings. The required price of carbon emissions is on the vertical axis, and the year is on the horizontal axis. The different colored columns represent the categories defined in the preceding paragraph.
The projected price for 2030 ranges from $135 to $5500 per metric ton of CO2e. The projected price in 2050 ranges from $245 to $13,000 per metric ton of CO2e. For comparison, at 11:22 a.m. CST on 12/4/18, Bloomberg reported the current price for emissions on the European Emissions Exchange was €20.72 ($23.48). Thus, the estimate for 2030 ranges from about 6 to 234 times the current price. I don’t know if fossil fuel prices would increase equally, but you can be sure they would increase a lot!
Carbon pricing, however, would not be sufficient in and of itself, and other policies would be required. The strategies mentioned in the report include using less energy, converting electricity generation to methods that don’t release carbon dioxide, converting all fuels to types that don’t release carbon dioxide, converting all energy end use to use decarbonized electricity (e.g. electric cars that run on renewable electricity), and some form of carbon sequestration. This is an intimidating list of changes. It would involve transforming basically all of our energy use infrastructure.
I couldn’t find an estimate of the cost of making the required transformation.
IPCC also doesn’t make specific predictions about the consequences of unchecked global warming, such as “Miami will flood,” or “400 million people will die of famine.” Rather, they speak of threats, how many people will be exposed to them, and which natural systems will be impacted. Figure 2 shows that for all of the systems considered, the threat increases the higher GMST goes. The increase in GMST is shown on the vertical axis. In the columns, white means the system will not impacted. Yellow means it will be impacted moderately. Red indicates that the impact will be severe and widespread. Purple indicates that the impacts will not only be severe, but perhaps irreversible, and also that the ability to cope with and adapt to the change will be limited. It is easy to see that for all systems, the risks increase as global warming increases. Some of the systems enter the red or purple color at or below 1.5C. But many of them only turn red or purple between 1.5 and 2.0°C.
The consequences are dramatic. The report discusses the specifics at great length, and they are far too numerous and complex to try to summarize here. However, I will say that the reports quotes estimates that, if no policy is instituted to limit global warming, GMST would rise 3.66°F by 2100, and it would reduce global Gross World Product (GWP) by 2.6%. According to the CIA World Factbook, GWP in 2017 was $127.8 trillion. Thus, even if GWP does not grow over time, a 2.6% reduction would equate to $3.3 trillion. In comparison, limiting global warming to 2°C would result in a decrease in GWP of 0.5% ($639 billion), and the 1.5°C scenario would result in a reduction of 0.3% ($383 billion).
Thus, the damage associated with global warming increases dramatically the more it warms. Limiting climate change to 1.5°C compared to 2.0°C would prevent $256 billion in economic loss every year. Thus, over a 10-year period, if you spent $2.5 trillion on climate change prevention, it would still be justifiable on the basis of avoided damage. A few trillion dollars here, hundreds of billions of dollars there – pretty soon, it will add up to real money!
The report includes population projections in its modeling of future climate change: increasing the population increases GHG emissions, and hence, it increases future climate change. The report does NOT address, however, limiting population as a strategy for limiting climate change, and least I could not find a section that did. Hmm! (If it’s there and I missed it, please let me know in a comment.)
The report is based on more than 6,000 scientific references. It contains a great deal of information, far too much to adequately summarize here. It should make clear, however, that the denial of climate change is no longer viable. If you ask me, it’s been clear for a long time, but this is pretty definitive.
Drastic change is required immediately if we are to avoid terrible damage to our planet. Even in only economic terms, the projected damage if we do nothing is absolutely staggering. Can humankind respond with the kind of immediate, large-scale planetary change that is required, or is it already too late?
Bloomberg.com. Markets: Energy. Viewed online 12/4/2018 at https://www.bloomberg.com/energ.
Central Intelligence Agency. 2018. The World Factbook 2016-17. Viewed online 11/30/2018 at https://www.cia.gov/library/publications/the-world-factbook/index.html.
Intergovernmental Panel on Climate Change. 2018. Global Warming of 1.5°C (Draft). Downloaded 11/24/2018 from https://www.ipcc.ch/report/sr15.
Can we limit global warming to 1.5°C? What would it require? Would there be real advantages compared to letting earth’s climate warm more than that? These are the questions that the Intergovernmental Panel on Climate Change (IPCC) Special Report 15, Global Warming of 1.5°C seeks to answer. IPCC is, of course, discussing human-induced global warming, not natural climate change. I will discuss their answer to the first question in this post, and the other two questions in the next post.
Let’s start by understanding what we can expect from this report.
Figure 1 shows an image of something. It appears to be something white. It is too far away and out of focus to see more. Figure 2 moves a little closer. Now it is possible to see that that it is a white rectangle with some gray smudges on it.
Figure 3 moves a little closer. You can’t see the whole of the white rectangle, but the gray smudges can now be seen to be a word: “Titanic.” But the writing is still out of focus. Figure 4 moves a little closer still, and the writing is now in clear focus.
Over the years, the IPCC has issued a series of reports on global warming/climate change. Over that time, the basic understanding of global warming has not changed. But as we have gotten closer, it has come more clearly into focus, and it has become possible to make out details that we couldn’t see before. We still don’t have global warming in full focus; we’re not to Figure 4 yet. But it has become possible to ask specific questions and give answers that, while not yet fully specific and detailed, are getting there. So, Global Warming of 1.5°C doesn’t contain radical new understandings. Rather, it is more detailed, and that is useful.
By the way, I chose the word “Titanic” on purpose. That ship was not built to survive a catastrophic iceberg strike, substandard steel may have been used to construct her, and she didn’t have enough lifeboats for all of the passengers. The captain denied the risk and sailed through the night into an iceberg field. By the time the iceberg was spotted dead ahead in the middle of the night, it was too late to turn and too late to stop. By that point, nothing they could do could change their fate: the Titanic was going to hit that berg and sink, and thousands were going to die.
Did I really write that? That’s really catastrophic, apocalyptic even! According to the IPCC report, we are very, very close to being like the Titanic. It may already be too late, but perhaps if we try really, really hard, it isn’t. Read on.
Human activity has already caused our planet’s global mean surface air temperature (GMST) to warm approximately 1°C (1.8°F) since pre-industrial times, according to the report. GMST is increasing by about 0.2°C (0.36°F) per decade. The rate of warming appears to be increasing. Figure 5 shows the temperature trend. The gray line shows the monthly temperatures in the datasets. The orange line shows the change forced by both humans and nature combined, while the yellow line shows the change forced by human activities alone (it is hard to see because it is embedded in the yellow band, look closely) .
GMST is an average across the globe. Some regions have warmed more than others. For instance, the temperature over land has increased more than the temperature over water; 40-60% of human population lives in regions that have already warmed 1.5°C (2.7°F) or more. Thus, a 1.5°C increase in GMST implies a larger than 1.5°C increase over land, with a smaller increase over the ocean.
Past emissions (through 2017) are probably not sufficient to cause GMST to increase more than 1.5°C. Therefore, warming limited to 1.5°C is theoretically possible if human emissions are immediately reduced. Two ways in which the 1.5°C limit could be achieved are discussed in the report. One reduces GHG emissions sufficiently quickly so that the 1.5°C limit is never exceeded. The other would allow a small overshoot of the limit, with temperature then being brought back within the limit by removing carbon dioxide from the atmosphere.
To limit the increase of GMST to 1.5°C with no overshoot would require GHG emissions of no more than 25-30 billion metric tons of CO2e per year in 2030 (compared to estimates that under business as usual they will be 50-58 billion metric tons per year). And GHG EMISSIONS WOULD NEED TO DECLINE TO NET ZERO BY 2050. That’s right – no net GHG emissions by 2050. Figure 6 shows the reductions over time in emissions of CO2, methane, black carbon (soot), and nitrous oxide consistent with a 1.5°C increase in GMST.
The no-net-emissions requirement could be met by two strategies: the first would involve reducing emissions themselves. Reducing emissions at this magnitude would require near-total transformations of our energy, transportation, and agricultural systems. The second would involve widely deploying carbon dioxide removal mechanisms. The only currently proven mechanism for removing carbon dioxide from the atmosphere is revegetation, especially reforestation. Attempts to add carbon capture and sequestration to power plants have not yet proven viable.
The limits agreed to in the Paris Climate Agreement are not sufficient to limit the increase in GMST to 1.5°C.
In the next post, I will look at what the report has to say about strategies to meet the limit, and what the costs and benefits might be.
Intergovernmental Panel on Climate Change. 2018. Global Warming of 1.5°C (Draft). Downloaded 11/24/2018 from https://www.ipcc.ch/report/sr15.
The last original post I made on this blog was September 27. I want to thank my readers for being patient with me while I struggled with my wife’s sudden illness and death. It has been difficult, and there has been an unbelievable amount to do. Hopefully I can now pick the blog back up and resume my once-weekly schedule of posts on Thursday mornings.
A couple of very important reports have come out since October 1 The first was the IPCC Special Report 15, Global Warming of 1.5°C. This report had been published online a few months previously, but had not completed the review process by the involved nations. It now has, and it is available for distribution and quotation. It still has some editing and layout revisions to undergo before the final copy is available, but the content has been approved.
This document is different from the IPCC assessment reports in that it seeks to answer a couple of basic questions: is it possible to limit the increase in global mean surface air temperature (GMST) to 1.5°C? What would be required to keep the increase within that limit? What would be the benefits and costs of doing so compared to a larger increase? It’s an important document, and the news is not encouraging.
The second is the Fourth National Climate Assessment published by the U.S. Global Change Research Program. This is the official U.S. government report on climate change, published every two years. This year, the authors felt that their understanding of how climate change would play-out has increased sufficiently to allow them to address its economic effect.
I’m not in love with economic analyses of environmental issues. Sometimes it is necessary to do uneconomic things. If all the values and services provided by the environment could be given an economic value that reflected their true worth, such an analysis might be possible. But we haven’t achieved that level of wisdom yet, so such analyses can be misleading. Still, this is an official government publication, and it is used by policymakers. Cost vs. benefit is an important consideration in making national policy, so it is important to have estimates of just how much climate change is going to impact the economy if we let it rampage unchecked. Again, the news is not good.
I will start with the IPCC report in my next post, and then move on to the National Climate Assessment.
Thanks for sticking with me.
I’m unable to write new posts for a couple of weeks. This is a rerun of one I published on 11/11/16, just after the election.
I expect Donald Trump to be a poor president. But it isn’t the end of the world, at least not yet.
It is time I addressed the elections of 2016 in this blog. Politics is far outside my focus here, yet the election has been a momentous event, and I don’t think I should ignore it completely.
I did not support Mr. Trump, nor did I support the slate of Republicans who ran the table in Missouri’s statewide elections. The environment is not a high priority for them, and some are overtly hostile to environmental concerns. I fear that their election is a mistake, and we will pay for it for many decades. Yet, the future is not set in stone, and we don’t yet know whether their actions in office will match their terrible rhetoric.
With that said, do not forget that this country has weathered many storms. The situation is not yet as dire as it was in 1812, when a foreign power invaded and burned our capital. Nor is it as dire as in 1860, when the South seceded from The Union. It is not as dire as it was in 1933, when unemployment was about 25%. It is not as dire as it was in the 1940s, when World War II broke out. “Keep calm and carry on.” It was good advice then, and it is good advice now.
We need to accept that Mr. Trump will be our next president, then we need to start moving into the future. There are a couple of things we need to do. We need to make our voices heard, and we need to be loud and clear about what is acceptable and what is not.
- Racism and bigotry are not okay, NEVER, EVER.
- Attacks on free speech are not okay, NEVER, EVER.
- Attacks on facts and science as the basis of knowledge are not okay, NEVER, EVER.
- Bullying and abuse are not okay, NEVER, EVER.
- Ignoring or being hostile to the environment is not okay, NEVER, EVER.
- (Today I would add that attacking the rule of law and the institutions that uphold it is not okay, NEVER, EVER.)
At the same time, the election results suggest that the status quo is not working for many people. When I was young, it was a fine thing to be liberal and progressive. But today in Missouri, the word “liberal” has become an epithet, and political adds hurl the word at opponents like mud. Did liberals earn that scorn? How? I don’t see much future in liberal policies until we are willing to look at what we have done that has offended so many.
I don’t have much hope that Mr. Trump is going to be a good president, but perhaps he will surprise us. Some who were supposed to become great presidents didn’t (Herbert Hoover), and some who were supposed to be lousy presidents became great (Abraham Lincoln). We’ll have to wait and see. Until then, here in St. Louis the sun is shining and it is a spectacular fall day. The world hasn’t failed yet. Keep calm and carry on.
Since publishing the above post, Mr. Trump has, in my opinion, proved himself to be one of the worst presidents in American history. He has had some policy successes, but in the process he has done huge damage to our country, both at home and abroad. It appears to me that he is intentionally trying to destroy the Environmental Protection Agency, or to make it a puppet of the corporations it is supposed to regulate. Worst of all, he has attacked and deliberately weakened the institutions that uphold the rule of law in America. This is damage that will be hard to repair, and we will pay for it for decades to come.
I’m unable to write new posts for a couple of weeks. This is a rerun of one I published 11/6/2016.
On 11/2/2016, the New York Times published an article by Farhad Manjoo on How the Internet Is Loosening Our Grip on the Truth. Manjoo wrote that the Internet, instead of delivering us into a “marketplace of ideas,” has led us into echo chambers dominated by preconceptions and biases. In those echo chambers, we hear only our preexisting beliefs endlessly repeated. Facts get evaluated through the lens of belief, and if they disagree with belief, they get ignored or denied. While not a new problem, he believes that the Internet is magnifying it. If he is right, it represents a serious problem for our democracy, which relies on the judgement of an informed public.
Psychologists and sociologist have known for a long time that we tend to see the world in ways that confirm preexisting beliefs, and they call it “confirmation bias.” There are many theories about why. One of my favorite explanations comes from a study that was done by Drew Westen and his colleagues during the 2004 presidential election. He took equal numbers of Republicans and Democrats and showed them self-contradictory statements by both Bush and Kerry. It took the subjects a moment to process what they had seen, but to nobody’s surprise, the Republicans explained away Bush’s contradiction and criticized Kerry for his. The Democrats did the inverse: they explained away Kerry’s contradiction, but criticized Bush for his. Thus, the subjects seemed to twist what they had seen, almost as if in a kaleidoscope, until it matched their preexisting beliefs.
So far, nothing new, just one of many demonstrations of confirmation bias. However, Westen added a wrinkle: while all this was going on, he had his subjects’ heads in a functional magnetic resonance imaging machine (fMRI). An fMRI measures the uptake of glucose by regions of the brain. Regions of the brain increase their uptake of glucose when they are being used. Thus, an fMRI provides a picture of which regions of the brain are active. The regions “light up” with color on the fMRI display.
Westen expected that while his subjects were busy processing, brain regions associated with thinking would light up. And when they achieved a resolution and spoke their opinion, then the brain would go quiet, at rest. But that is not what he found. He found that while his subjects were thinking, the regions of the brain that lit up were the regions associated with emotional pain. And when they spoke their opinion, the brain didn’t go quiet. Instead, the pleasure centers of the brain lit up. These are the regions of the brain that light up when a person takes a dose of a narcotic.
Thus, Westen’s conclusion was that we experience facts that contradict our preconceived ideas as pain. And when we twist reality to conform to our ideas, the pain goes away, and we get a “hit” of pleasure like taking a narcotic.
No wonder we do it. And those echo chambers that Manjoo mentioned? That’s where we go, like opium dens, to get hit after hit of our favorite narcotic.
That is why Mogreenstats focuses on large-scale studies. I diverge into other stuff from time-to-time, but mostly I focus on statistics about the environment. I see it as an antidote to the propaganda one hears about the environment, whichever echo chamber it comes from. No, these studies aren’t perfect. But I see them as being as close as one can get to actual facts. If we don’t base our public policy on facts, it is not likely to be effective.
Westen, Drew, Pavel Blagov, Keith Harenski, Clint Kilts, and Stephan Hamann. 2006. “Neural Bases of Motivated Reasoning: An fMRI Study of Emotional Constraints on Partisan Political Judgement in the 2004 U.S. Presidential Election. Journal of Cognitive Neuroscience. 18(11), p. 1947-1958. Viewed online 11/2/2016 at http://birc.jaredjustus.com/assets/publications/Westen,%20Kilts%202006%20J%20Cognit%20Neurosci.pdf.
Wikipedia. Drew Westen. Viewed online 11/2/2016 at https://en.wikipedia.org/wiki/Drew_Westen.